[android] support adding image attachments to private messages

2026-02-13 03:09:04 +01:00 · 2018-11-20 19:30:33 -02:00
parent 52ec56d690
commit 800dfed5c1
17 changed files with 438 additions and 66 deletions
--- a/briar-android/src/main/java/org/briarproject/briar/android/TestingConstants.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/TestingConstants.java
@@ -30,4 +30,10 @@ public interface TestingConstants {
 	long EXPIRY_DATE = IS_DEBUG_BUILD || IS_BETA_BUILD ?
 			BuildConfig.BuildTimestamp + 90 * 24 * 60 * 60 * 1000L :
 			Long.MAX_VALUE;
+
+	/**
+	 * Feature flag for enabling image attachments.
+	 */
+	boolean FEATURE_FLAG_IMAGE_ATTACHMENTS = IS_DEBUG_BUILD;
+
 }
--- a/briar-android/src/main/java/org/briarproject/briar/android/activity/RequestCodes.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/activity/RequestCodes.java
@@ -14,5 +14,6 @@ public interface RequestCodes {
 	int REQUEST_BLUETOOTH_DISCOVERABLE = 10;
 	int REQUEST_UNLOCK = 11;
 	int REQUEST_KEYGUARD_UNLOCK = 12;
+	int REQUEST_ATTACH_IMAGE = 13;

 }
--- a/briar-android/src/main/java/org/briarproject/briar/android/blog/ReblogFragment.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/blog/ReblogFragment.java
@@ -1,5 +1,6 @@
 package org.briarproject.briar.android.blog;

+import android.net.Uri;
 import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -20,6 +21,8 @@ import org.briarproject.briar.android.fragment.BaseFragment;
 import org.briarproject.briar.android.view.TextInputView;
 import org.briarproject.briar.android.view.TextInputView.TextInputListener;

+import java.util.List;
+
 import javax.annotation.Nullable;
 import javax.inject.Inject;

@@ -118,10 +121,9 @@ public class ReblogFragment extends BaseFragment implements TextInputListener {
 	}

 	@Override
-	public void onSendClick(String text) {
+	public void onSendClick(@Nullable String text, List<Uri> imageUris) {
 		ui.input.hideSoftKeyboard();
-		String comment = getComment();
-		feedController.repeatPost(item, comment,
+		feedController.repeatPost(item, text,
 				new UiExceptionHandler<DbException>(this) {
 					@Override
 					public void onExceptionUi(DbException exception) {
@@ -131,12 +133,6 @@ public class ReblogFragment extends BaseFragment implements TextInputListener {
 		finish();
 	}

-	@Nullable
-	private String getComment() {
-		if (ui.input.getText().length() == 0) return null;
-		return ui.input.getText().toString();
-	}
-
 	private void showProgressBar() {
 		ui.progressBar.setVisibility(VISIBLE);
 		ui.input.setVisibility(GONE);
--- a/briar-android/src/main/java/org/briarproject/briar/android/blog/WriteBlogPostActivity.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/blog/WriteBlogPostActivity.java
@@ -1,7 +1,9 @@
 package org.briarproject.briar.android.blog;

 import android.content.Intent;
+import android.net.Uri;
 import android.os.Bundle;
+import android.support.annotation.Nullable;
 import android.text.Editable;
 import android.text.TextWatcher;
 import android.view.KeyEvent;
@@ -14,8 +16,9 @@ import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.identity.IdentityManager;
 import org.briarproject.bramble.api.identity.LocalAuthor;
+import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
+import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.bramble.api.sync.GroupId;
-import org.briarproject.bramble.util.StringUtils;
 import org.briarproject.briar.R;
 import org.briarproject.briar.android.activity.ActivityComponent;
 import org.briarproject.briar.android.activity.BriarActivity;
@@ -27,6 +30,7 @@ import org.briarproject.briar.api.blog.BlogPost;
 import org.briarproject.briar.api.blog.BlogPostFactory;

 import java.security.GeneralSecurityException;
+import java.util.List;
 import java.util.logging.Logger;

 import javax.inject.Inject;
@@ -35,8 +39,12 @@ import static android.view.View.GONE;
 import static android.view.View.VISIBLE;
 import static java.util.logging.Level.WARNING;
 import static org.briarproject.bramble.util.LogUtils.logException;
+import static org.briarproject.bramble.util.StringUtils.isNullOrEmpty;
+import static org.briarproject.bramble.util.StringUtils.truncateUtf8;
 import static org.briarproject.briar.api.blog.BlogConstants.MAX_BLOG_POST_TEXT_LENGTH;

+@MethodsNotNullByDefault
+@ParametersNotNullByDefault
 public class WriteBlogPostActivity extends BriarActivity
 		implements OnEditorActionListener, TextInputListener {

@@ -58,9 +66,8 @@ public class WriteBlogPostActivity extends BriarActivity
 	@Inject
 	volatile BlogManager blogManager;

-	@SuppressWarnings("ConstantConditions")
 	@Override
-	public void onCreate(Bundle state) {
+	public void onCreate(@Nullable Bundle state) {
 		super.onCreate(state);

 		Intent i = getIntent();
@@ -128,17 +135,19 @@ public class WriteBlogPostActivity extends BriarActivity
 	}

 	private void enableOrDisablePublishButton() {
-		input.setSendButtonEnabled(input.getText().length() > 0);
+		input.setSendButtonEnabled(!input.isEmpty());
 	}

 	@Override
-	public void onSendClick(String text) {
+	public void onSendClick(@Nullable String text, List<Uri> imageUris) {
+		if (isNullOrEmpty(text)) return;
+
 		// hide publish button, show progress bar
 		input.hideSoftKeyboard();
 		input.setVisibility(GONE);
 		progressBar.setVisibility(VISIBLE);

-		text = StringUtils.truncateUtf8(text, MAX_BLOG_POST_TEXT_LENGTH);
+		text = truncateUtf8(text, MAX_BLOG_POST_TEXT_LENGTH);
 		storePost(text);
 	}

--- a/briar-android/src/main/java/org/briarproject/briar/android/conversation/ConversationActivity.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/conversation/ConversationActivity.java
@@ -6,6 +6,7 @@ import android.arch.lifecycle.ViewModelProvider;
 import android.arch.lifecycle.ViewModelProviders;
 import android.content.DialogInterface;
 import android.content.Intent;
+import android.net.Uri;
 import android.os.Bundle;
 import android.support.annotation.Nullable;
 import android.support.annotation.UiThread;
@@ -52,7 +53,6 @@ import org.briarproject.bramble.api.sync.Message;
 import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.bramble.api.sync.event.MessagesAckedEvent;
 import org.briarproject.bramble.api.sync.event.MessagesSentEvent;
-import org.briarproject.bramble.util.StringUtils;
 import org.briarproject.briar.R;
 import org.briarproject.briar.android.activity.ActivityComponent;
 import org.briarproject.briar.android.activity.BriarActivity;
@@ -64,6 +64,7 @@ import org.briarproject.briar.android.introduction.IntroductionActivity;
 import org.briarproject.briar.android.privategroup.conversation.GroupActivity;
 import org.briarproject.briar.android.view.BriarRecyclerView;
 import org.briarproject.briar.android.view.TextInputView;
+import org.briarproject.briar.android.view.TextInputView.AttachImageListener;
 import org.briarproject.briar.android.view.TextInputView.TextInputListener;
 import org.briarproject.briar.api.android.AndroidNotificationManager;
 import org.briarproject.briar.api.blog.BlogSharingManager;
@@ -106,6 +107,7 @@ import static android.support.v4.app.ActivityOptionsCompat.makeSceneTransitionAn
 import static android.support.v4.view.ViewCompat.setTransitionName;
 import static android.support.v7.util.SortedList.INVALID_POSITION;
 import static android.view.Gravity.RIGHT;
+import static android.widget.Toast.LENGTH_LONG;
 import static android.widget.Toast.LENGTH_SHORT;
 import static java.util.Collections.emptyList;
 import static java.util.Collections.sort;
@@ -115,6 +117,10 @@ import static java.util.logging.Level.WARNING;
 import static org.briarproject.bramble.util.LogUtils.logDuration;
 import static org.briarproject.bramble.util.LogUtils.logException;
 import static org.briarproject.bramble.util.LogUtils.now;
+import static org.briarproject.bramble.util.StringUtils.isNullOrEmpty;
+import static org.briarproject.bramble.util.StringUtils.truncateUtf8;
+import static org.briarproject.briar.android.TestingConstants.FEATURE_FLAG_IMAGE_ATTACHMENTS;
+import static org.briarproject.briar.android.activity.RequestCodes.REQUEST_ATTACH_IMAGE;
 import static org.briarproject.briar.android.activity.RequestCodes.REQUEST_INTRODUCTION;
 import static org.briarproject.briar.android.conversation.ImageActivity.ATTACHMENT;
 import static org.briarproject.briar.android.conversation.ImageActivity.DATE;
@@ -131,7 +137,7 @@ import static uk.co.samuelwall.materialtaptargetprompt.MaterialTapTargetPrompt.S
@ParametersNotNullByDefault
 public class ConversationActivity extends BriarActivity
 		implements EventListener, ConversationListener, TextInputListener,
-		TextCache, AttachmentCache {
+		TextCache, AttachmentCache, AttachImageListener {

 	public static final String CONTACT_ID = "briar.CONTACT_ID";

@@ -251,6 +257,9 @@ public class ConversationActivity extends BriarActivity

 		textInputView = findViewById(R.id.text_input_container);
 		textInputView.setListener(this);
+		if (FEATURE_FLAG_IMAGE_ATTACHMENTS) {
+			textInputView.setAttachImageListener(this);
+		}
 	}

 	@Override
@@ -267,6 +276,8 @@ public class ConversationActivity extends BriarActivity
 					Snackbar.LENGTH_SHORT);
 			snackbar.getView().setBackgroundResource(R.color.briar_primary);
 			snackbar.show();
+		} else if (request == REQUEST_ATTACH_IMAGE && result == RESULT_OK) {
+			textInputView.onImageReceived(data);
 		}
 	}

@@ -573,9 +584,19 @@ public class ConversationActivity extends BriarActivity
 	}

 	@Override
-	public void onSendClick(String text) {
-		if (text.isEmpty()) return;
-		text = StringUtils.truncateUtf8(text, MAX_PRIVATE_MESSAGE_TEXT_LENGTH);
+	public void onAttachImage(Intent intent) {
+		startActivityForResult(intent, REQUEST_ATTACH_IMAGE);
+	}
+
+	@Override
+	public void onSendClick(@Nullable String text, List<Uri> imageUris) {
+		if (!imageUris.isEmpty()) {
+			Toast.makeText(this, "Not yet implemented.", LENGTH_LONG).show();
+			textInputView.setText("");
+			return;
+		}
+		if (isNullOrEmpty(text)) return;
+		text = truncateUtf8(text, MAX_PRIVATE_MESSAGE_TEXT_LENGTH);
 		long timestamp = System.currentTimeMillis();
 		timestamp = Math.max(timestamp, getMinTimestampForNewMessage());
 		if (messagingGroupId == null) loadGroupId(text, timestamp);
--- a/briar-android/src/main/java/org/briarproject/briar/android/introduction/IntroductionMessageFragment.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/introduction/IntroductionMessageFragment.java
@@ -1,8 +1,8 @@
 package org.briarproject.briar.android.introduction;

 import android.content.Context;
+import android.net.Uri;
 import android.os.Bundle;
-import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.v7.app.ActionBar;
 import android.view.LayoutInflater;
@@ -17,7 +17,8 @@ import org.briarproject.bramble.api.contact.Contact;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.contact.ContactManager;
 import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.util.StringUtils;
+import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
+import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.briar.R;
 import org.briarproject.briar.android.activity.ActivityComponent;
 import org.briarproject.briar.android.fragment.BaseFragment;
@@ -25,6 +26,7 @@ import org.briarproject.briar.android.view.TextInputView;
 import org.briarproject.briar.android.view.TextInputView.TextInputListener;
 import org.briarproject.briar.api.introduction.IntroductionManager;

+import java.util.List;
 import java.util.logging.Logger;

 import javax.inject.Inject;
@@ -38,9 +40,12 @@ import static android.view.View.VISIBLE;
 import static android.widget.Toast.LENGTH_SHORT;
 import static java.util.logging.Level.WARNING;
 import static org.briarproject.bramble.util.LogUtils.logException;
+import static org.briarproject.bramble.util.StringUtils.truncateUtf8;
 import static org.briarproject.briar.android.util.UiUtils.getContactDisplayName;
 import static org.briarproject.briar.api.introduction.IntroductionConstants.MAX_INTRODUCTION_TEXT_LENGTH;

+@MethodsNotNullByDefault
+@ParametersNotNullByDefault
 public class IntroductionMessageFragment extends BaseFragment
 		implements TextInputListener {

@@ -84,8 +89,9 @@ public class IntroductionMessageFragment extends BaseFragment
 	}

 	@Override
-	public View onCreateView(@NonNull LayoutInflater inflater,
-			ViewGroup container, Bundle savedInstanceState) {
+	public View onCreateView(LayoutInflater inflater,
+			@Nullable ViewGroup container,
+			@Nullable Bundle savedInstanceState) {

 		// change toolbar text
 		ActionBar actionBar = introductionActivity.getSupportActionBar();
@@ -184,14 +190,14 @@ public class IntroductionMessageFragment extends BaseFragment
 	}

 	@Override
-	public void onSendClick(@NonNull String text) {
+	public void onSendClick(@Nullable String text, List<Uri> imageUris) {
 		// disable button to prevent accidental double invitations
 		ui.message.setSendButtonEnabled(false);

-		String txt = ui.message.getText().toString();
-		if (txt.isEmpty()) txt = null;
-		else txt = StringUtils.truncateUtf8(txt, MAX_INTRODUCTION_TEXT_LENGTH);
-		makeIntroduction(contact1, contact2, txt);
+		if (text != null) {
+			text = truncateUtf8(text, MAX_INTRODUCTION_TEXT_LENGTH);
+		}
+		makeIntroduction(contact1, contact2, text);

 		// don't wait for the introduction to be made before finishing activity
 		introductionActivity.hideSoftKeyboard(ui.message);
--- a/briar-android/src/main/java/org/briarproject/briar/android/sharing/BaseMessageFragment.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/sharing/BaseMessageFragment.java
@@ -1,7 +1,9 @@
 package org.briarproject.briar.android.sharing;

 import android.content.Context;
+import android.net.Uri;
 import android.os.Bundle;
+import android.support.annotation.Nullable;
 import android.support.annotation.StringRes;
 import android.support.annotation.UiThread;
 import android.support.design.widget.Snackbar;
@@ -10,17 +12,23 @@ import android.view.MenuItem;
 import android.view.View;
 import android.view.ViewGroup;

+import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.briar.R;
 import org.briarproject.briar.android.fragment.BaseFragment;
 import org.briarproject.briar.android.view.LargeTextInputView;
 import org.briarproject.briar.android.view.TextInputView.TextInputListener;

+import java.util.List;
+
 import static android.support.design.widget.Snackbar.LENGTH_SHORT;
 import static org.briarproject.bramble.util.StringUtils.truncateUtf8;
 import static org.briarproject.bramble.util.StringUtils.utf8IsTooLong;
 import static org.briarproject.briar.api.sharing.SharingConstants.MAX_INVITATION_TEXT_LENGTH;

+@MethodsNotNullByDefault
+@ParametersNotNullByDefault
 public abstract class BaseMessageFragment extends BaseFragment
 		implements TextInputListener {

@@ -34,8 +42,9 @@ public abstract class BaseMessageFragment extends BaseFragment
 	}

 	@Override
-	public View onCreateView(LayoutInflater inflater, ViewGroup container,
-			Bundle savedInstanceState) {
+	public View onCreateView(@Nullable LayoutInflater inflater,
+			@Nullable ViewGroup container,
+			@Nullable Bundle savedInstanceState) {

 		// inflate view
 		View v = inflater.inflate(R.layout.fragment_message, container,
@@ -76,7 +85,8 @@ public abstract class BaseMessageFragment extends BaseFragment
 	}

 	@Override
-	public void onSendClick(String text) {
+	public void onSendClick(@Nullable String text, List<Uri> imageUris) {
+		if (text == null) return;
 		if (utf8IsTooLong(text, listener.getMaximumTextLength())) {
 			Snackbar.make(message, R.string.text_too_long, LENGTH_SHORT).show();
 			return;
--- a/briar-android/src/main/java/org/briarproject/briar/android/threaded/ThreadListActivity.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/threaded/ThreadListActivity.java
@@ -1,6 +1,7 @@
 package org.briarproject.briar.android.threaded;

 import android.content.Intent;
+import android.net.Uri;
 import android.os.Bundle;
 import android.support.annotation.CallSuper;
 import android.support.annotation.StringRes;
@@ -33,6 +34,7 @@ import org.briarproject.briar.api.client.NamedGroup;
 import org.thoughtcrime.securesms.components.KeyboardAwareLinearLayout;

 import java.util.Collection;
+import java.util.List;
 import java.util.logging.Logger;

 import javax.annotation.Nullable;
@@ -348,8 +350,8 @@ public abstract class ThreadListActivity<G extends NamedGroup, I extends ThreadI
 	}

 	@Override
-	public void onSendClick(String text) {
-		if (text.trim().length() == 0)
+	public void onSendClick(@Nullable String text, List<Uri> imageUris) {
+		if (text == null || text.trim().length() == 0)
 			return;
 		if (utf8IsTooLong(text, getMaxTextLength())) {
 			displaySnackbar(R.string.text_too_long);
--- a/briar-android/src/main/java/org/briarproject/briar/android/view/TextInputAttachmentController.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/view/TextInputAttachmentController.java
@@ -0,0 +1,211 @@
+package org.briarproject.briar.android.view;
+
+import android.content.ClipData;
+import android.content.Intent;
+import android.graphics.Bitmap;
+import android.net.Uri;
+import android.support.annotation.Nullable;
+import android.support.annotation.UiThread;
+import android.support.design.widget.FloatingActionButton;
+import android.support.v7.graphics.Palette;
+import android.support.v7.widget.AppCompatImageButton;
+import android.text.Editable;
+import android.text.TextWatcher;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ImageView;
+
+import com.bumptech.glide.load.DataSource;
+import com.bumptech.glide.load.engine.GlideException;
+import com.bumptech.glide.request.RequestListener;
+import com.bumptech.glide.request.target.Target;
+import com.vanniktech.emoji.EmojiEditText;
+
+import org.briarproject.briar.R;
+import org.briarproject.briar.android.conversation.glide.GlideApp;
+import org.briarproject.briar.android.view.TextInputView.AttachImageListener;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import static android.content.Intent.ACTION_GET_CONTENT;
+import static android.content.Intent.ACTION_OPEN_DOCUMENT;
+import static android.content.Intent.CATEGORY_OPENABLE;
+import static android.content.Intent.EXTRA_ALLOW_MULTIPLE;
+import static android.graphics.Color.BLACK;
+import static android.graphics.Color.WHITE;
+import static android.os.Build.VERSION.SDK_INT;
+import static android.support.v7.app.AppCompatDelegate.MODE_NIGHT_YES;
+import static android.support.v7.app.AppCompatDelegate.getDefaultNightMode;
+import static android.view.View.GONE;
+import static android.view.View.INVISIBLE;
+import static android.view.View.VISIBLE;
+import static com.bumptech.glide.load.engine.DiskCacheStrategy.NONE;
+import static com.bumptech.glide.load.resource.bitmap.DownsampleStrategy.FIT_CENTER;
+import static java.util.Collections.emptyList;
+import static java.util.Collections.singletonList;
+
+class TextInputAttachmentController implements TextWatcher {
+
+	private final EmojiEditText editText;
+	private final View sendButton;
+	private final AppCompatImageButton imageButton;
+	private final ViewGroup imageLayout;
+	private final ImageView imageView;
+
+	private final AttachImageListener listener;
+
+	private String textHint;
+	private List<Uri> imageUris = emptyList();
+
+	public TextInputAttachmentController(View v, EmojiEditText editText,
+			View sendButton, AttachImageListener listener) {
+
+		imageLayout = v.findViewById(R.id.imageLayout);
+		imageView = v.findViewById(R.id.imageView);
+		FloatingActionButton imageCancelButton =
+				v.findViewById(R.id.imageCancelButton);
+		imageButton = v.findViewById(R.id.imageButton);
+
+		this.listener = listener;
+		this.sendButton = sendButton;
+		this.editText = editText;
+		this.textHint = editText.getHint().toString();
+
+		editText.addTextChangedListener(this);
+		imageButton.setOnClickListener(view -> onImageButtonClicked());
+		imageCancelButton.setOnClickListener(view -> afterSendButtonClicked());
+		showImageButton(true);
+	}
+
+	private void onImageButtonClicked() {
+		Intent intent = new Intent(SDK_INT >= 19 ?
+				ACTION_OPEN_DOCUMENT : ACTION_GET_CONTENT);
+		intent.addCategory(CATEGORY_OPENABLE);
+		intent.setType("image/*");
+		if (SDK_INT >= 18)
+			intent.putExtra(EXTRA_ALLOW_MULTIPLE, false);
+		listener.onAttachImage(intent);
+	}
+
+	void onImageReceived(@Nullable Intent resultData) {
+		if (resultData == null) return;
+		if (resultData.getData() != null) {
+			imageUris = singletonList(resultData.getData());
+		} else if (SDK_INT >= 18 && resultData.getClipData() != null) {
+			ClipData clipData = resultData.getClipData();
+			imageUris = new ArrayList<>(clipData.getItemCount());
+			for (int i = 0; i < clipData.getItemCount(); i++) {
+				imageUris.add(clipData.getItemAt(i).getUri());
+			}
+		} else {
+			return;
+		}
+		showImageButton(false);
+		editText.setHint(R.string.image_caption_hint);
+		imageLayout.setVisibility(VISIBLE);
+		GlideApp.with(imageView)
+				.asBitmap()
+				.load(imageUris.get(0))  // TODO show more than the first
+				.diskCacheStrategy(NONE)
+				.downsample(FIT_CENTER)
+				.addListener(new RequestListener<Bitmap>() {
+					@Override
+					public boolean onLoadFailed(@Nullable GlideException e,
+							Object model, Target<Bitmap> target,
+							boolean isFirstResource) {
+						return false;
+					}
+
+					@Override
+					public boolean onResourceReady(Bitmap resource,
+							Object model, Target<Bitmap> target,
+							DataSource dataSource, boolean isFirstResource) {
+						Palette.from(resource).generate(
+								TextInputAttachmentController.this::onPaletteGenerated);
+						return false;
+					}
+				})
+				.into(imageView);
+	}
+
+	@UiThread
+	private void onPaletteGenerated(@Nullable Palette palette) {
+		int color;
+		if (palette == null) {
+			color = getDefaultNightMode() == MODE_NIGHT_YES ? BLACK : WHITE;
+		} else {
+			color = getDefaultNightMode() == MODE_NIGHT_YES ?
+					palette.getDarkMutedColor(BLACK) :
+					palette.getLightMutedColor(WHITE);
+		}
+		imageView.setBackgroundColor(color);
+	}
+
+	private void showImageButton(boolean showImageButton) {
+		if (showImageButton) {
+			imageButton.setVisibility(VISIBLE);
+			if (SDK_INT <= 15) {
+				sendButton.setVisibility(INVISIBLE);
+			} else {
+				sendButton.clearAnimation();
+				sendButton.animate().alpha(0f).withEndAction(
+						() -> sendButton.setVisibility(INVISIBLE)
+				).start();
+				imageButton.clearAnimation();
+				imageButton.animate().alpha(1f).start();
+			}
+		} else {
+			sendButton.setVisibility(VISIBLE);
+			if (SDK_INT <= 15) {
+				imageButton.setVisibility(INVISIBLE);
+			} else {
+				sendButton.clearAnimation();
+				sendButton.animate().alpha(1f).start();
+				imageButton.clearAnimation();
+				imageButton.animate().alpha(0f).withEndAction(
+						() -> imageButton.setVisibility(INVISIBLE)
+				).start();
+			}
+		}
+	}
+
+	@Override
+	public void beforeTextChanged(CharSequence s, int start, int count,
+			int after) {
+		// noop
+	}
+
+	@Override
+	public void onTextChanged(CharSequence s, int start, int before,
+			int count) {
+		if (start != 0 || !imageUris.isEmpty()) return;
+		if (s.length() > 0) showImageButton(false);
+		else if (s.length() == 0) showImageButton(true);
+	}
+
+	@Override
+	public void afterTextChanged(Editable s) {
+		// noop
+	}
+
+	public List<Uri> getUris() {
+		return imageUris;
+	}
+
+	public void saveHint(String hint) {
+		textHint = hint;
+	}
+
+	void afterSendButtonClicked() {
+		// restore hint
+		editText.setHint(textHint);
+		// hide image layout
+		imageLayout.setVisibility(GONE);
+		// reset image URIs
+		imageUris = emptyList();
+		// show the image button again, so images can get attached
+		showImageButton(true);
+	}
+
+}
--- a/briar-android/src/main/java/org/briarproject/briar/android/view/TextInputView.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/view/TextInputView.java
@@ -2,10 +2,13 @@ package org.briarproject.briar.android.view;

 import android.animation.LayoutTransition;
 import android.content.Context;
+import android.content.Intent;
 import android.content.res.TypedArray;
 import android.graphics.Rect;
+import android.net.Uri;
 import android.os.IBinder;
 import android.support.annotation.CallSuper;
+import android.support.annotation.Nullable;
 import android.support.annotation.StringRes;
 import android.support.annotation.UiThread;
 import android.support.v7.widget.AppCompatImageButton;
@@ -26,13 +29,16 @@ import org.briarproject.briar.R;
 import org.briarproject.briar.android.BriarApplication;
 import org.thoughtcrime.securesms.components.KeyboardAwareLinearLayout;

-import javax.annotation.Nullable;
+import java.util.List;
+
 import javax.inject.Inject;

 import static android.content.Context.INPUT_METHOD_SERVICE;
 import static android.content.Context.LAYOUT_INFLATER_SERVICE;
 import static android.view.KeyEvent.KEYCODE_ENTER;
 import static android.view.inputmethod.InputMethodManager.SHOW_IMPLICIT;
+import static java.util.Collections.emptyList;
+import static java.util.Objects.requireNonNull;

@UiThread
@MethodsNotNullByDefault
@@ -44,6 +50,8 @@ public class TextInputView extends KeyboardAwareLinearLayout {

 	@Nullable
 	TextInputListener listener;
+	@Nullable
+	TextInputAttachmentController attachmentController;

 	AppCompatImageButton emojiToggle;
 	EmojiEditText editText;
@@ -69,12 +77,12 @@ public class TextInputView extends KeyboardAwareLinearLayout {
 		setOrientation(VERTICAL);
 		setLayoutTransition(new LayoutTransition());
 		inflateLayout(context);
-		setUpViews(context, attrs);
+		if (!isInEditMode()) setUpViews(context, attrs);
 	}

 	protected void inflateLayout(Context context) {
-		LayoutInflater inflater = (LayoutInflater) context
-				.getSystemService(LAYOUT_INFLATER_SERVICE);
+		LayoutInflater inflater = (LayoutInflater) requireNonNull(
+				context.getSystemService(LAYOUT_INFLATER_SERVICE));
 		inflater.inflate(R.layout.text_input_view, this, true);
 	}

@@ -96,18 +104,33 @@ public class TextInputView extends KeyboardAwareLinearLayout {
 		String hint = attributes.getString(R.styleable.TextInputView_hint);
 		attributes.recycle();

-		if (hint != null) editText.setHint(hint);
+		if (hint != null) setHint(hint);

 		emojiToggle.setOnClickListener(v -> emojiPopup.toggle());
 		editText.setOnClickListener(v -> showSoftKeyboard());
 		editText.setOnKeyListener((v, keyCode, event) -> {
 			if (keyCode == KEYCODE_ENTER && event.isCtrlPressed()) {
-				trySendMessage();
+				onSendButtonClicked();
 				return true;
 			}
 			return false;
 		});
-		sendButton.setOnClickListener(v -> trySendMessage());
+		sendButton.setOnClickListener(v -> onSendButtonClicked());
+	}
+
+	public void setListener(TextInputListener listener) {
+		this.listener = listener;
+	}
+
+	/**
+	 * Call this during onCreate() to enable image attachment support.
+	 * Do not call it twice!
+	 */
+	public void setAttachImageListener(AttachImageListener imageListener) {
+		if (attachmentController != null) throw new IllegalStateException();
+		attachmentController = new TextInputAttachmentController(getRootView(),
+				editText, sendButton, imageListener
+		);
 	}

 	private void showEmojiIcon() {
@@ -118,10 +141,23 @@ public class TextInputView extends KeyboardAwareLinearLayout {
 		emojiToggle.setImageResource(R.drawable.ic_keyboard);
 	}

-	private void trySendMessage() {
+	private void onSendButtonClicked() {
 		if (listener != null) {
-			listener.onSendClick(editText.getText().toString());
+			Editable editable = editText.getText();
+			String text = editable == null || editable.length() == 0 ?
+					null : editable.toString();
+			List<Uri> imageUris = attachmentController == null ? emptyList() :
+					attachmentController.getUris();
+			listener.onSendClick(text, imageUris);
 		}
+		if (attachmentController != null) {
+			attachmentController.afterSendButtonClicked();
+		}
+	}
+
+	public void onImageReceived(@Nullable Intent resultData) {
+		if (attachmentController == null) throw new IllegalStateException();
+		attachmentController.onImageReceived(resultData);
 	}

 	@Override
@@ -139,12 +175,17 @@ public class TextInputView extends KeyboardAwareLinearLayout {
 		editText.setText(text);
 	}

-	public Editable getText() {
-		return editText.getText();
+	public boolean isEmpty() {
+		return editText.getText() == null || editText.getText().length() == 0;
 	}

 	public void setHint(@StringRes int res) {
-		editText.setHint(res);
+		setHint(getContext().getString(res));
+	}
+
+	public void setHint(String hint) {
+		if (attachmentController != null) attachmentController.saveHint(hint);
+		editText.setHint(hint);
 	}

 	public void setSendButtonEnabled(boolean enabled) {
@@ -155,24 +196,26 @@ public class TextInputView extends KeyboardAwareLinearLayout {
 		editText.addTextChangedListener(watcher);
 	}

-	public void setListener(TextInputListener listener) {
-		this.listener = listener;
-	}
-
 	public void showSoftKeyboard() {
 		Object o = getContext().getSystemService(INPUT_METHOD_SERVICE);
-		((InputMethodManager) o).showSoftInput(editText, SHOW_IMPLICIT);
+		InputMethodManager imm = (InputMethodManager) requireNonNull(o);
+		imm.showSoftInput(editText, SHOW_IMPLICIT);
 	}

 	public void hideSoftKeyboard() {
 		if (emojiPopup.isShowing()) emojiPopup.dismiss();
 		IBinder token = editText.getWindowToken();
 		Object o = getContext().getSystemService(INPUT_METHOD_SERVICE);
-		((InputMethodManager) o).hideSoftInputFromWindow(token, 0);
+		InputMethodManager imm = (InputMethodManager) requireNonNull(o);
+		imm.hideSoftInputFromWindow(token, 0);
+	}
+
+	public interface AttachImageListener {
+		void onAttachImage(Intent intent);
 	}

 	public interface TextInputListener {
-		void onSendClick(String text);
+		void onSendClick(@Nullable String text, List<Uri> imageUris);
 	}

 }