app list: open keyboard when X-ing search query

app/src/main/java/org/fdroid/fdroid/Utils.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2010-12  Ciaran Gultnieks, ciaran@ciarang.com
+ * Copyright (C) 2019 Michael Pöhn, michael.poehn@fsfe.org
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -25,6 +26,7 @@ import android.content.pm.Signature;
 import android.content.res.Resources;
 import android.database.Cursor;
 import android.graphics.Bitmap;
+import android.graphics.Rect;
 import android.net.Uri;
 import android.os.Build;
 import android.os.Handler;
@@ -45,6 +47,8 @@ import android.text.style.TypefaceSpan;
 import android.util.DisplayMetrics;
 import android.util.Log;
 import android.util.TypedValue;
+import android.view.View;
+import android.view.ViewTreeObserver;
 import android.widget.Toast;
 import com.nostra13.universalimageloader.core.DisplayImageOptions;
 import com.nostra13.universalimageloader.core.assist.ImageScaleType;
@@ -912,4 +916,35 @@ public final class Utils {
             return true;
         }
     }
+
+    /**
+     * Keep an instance of this class as an field in an Activity for figuring out whether the on
+     * screen keyboard is currently visible or not.
+     */
+    public static class KeyboardStateMonitor {
+
+        private boolean visible = false;
+
+        /**
+         * @param contentView this must be the top most Container of the layout used by the Activity
+         */
+        public KeyboardStateMonitor(final View contentView) {
+            contentView.getViewTreeObserver().addOnGlobalLayoutListener(
+                    new ViewTreeObserver.OnGlobalLayoutListener() {
+                        @Override
+                        public void onGlobalLayout() {
+                            int screenHeight = contentView.getRootView().getHeight();
+                            Rect rect = new Rect();
+                            contentView.getWindowVisibleDisplayFrame(rect);
+                            int keypadHeight = screenHeight - rect.bottom;
+                            visible = keypadHeight >= screenHeight * 0.15;
+                        }
+                    }
+            );
+        }
+
+        public boolean isKeyboardVisible() {
+            return visible;
+        }
+    }
 }

app/src/main/java/org/fdroid/fdroid/views/apps/AppListActivity.java

@@ -1,5 +1,26 @@
+/*
+ * Copyright (C) 2016-17 Peter Serwylo,
+ * Copyright (C) 2017-18 Hans-Christoph Steiner
+ * Copyright (C) 2019 Michael Pöhn, michael.poehn@fsfe.org
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 3
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
 package org.fdroid.fdroid.views.apps;
 
+import android.content.Context;
 import android.content.Intent;
 import android.database.Cursor;
 import android.os.Bundle;
@@ -21,6 +42,7 @@ import android.widget.TextView;
 import com.nostra13.universalimageloader.core.ImageLoader;
 import org.fdroid.fdroid.FDroidApp;
 import org.fdroid.fdroid.R;
+import org.fdroid.fdroid.Utils;
 import org.fdroid.fdroid.data.AppProvider;
 import org.fdroid.fdroid.data.Schema;
 
@@ -43,6 +65,7 @@ public class AppListActivity extends AppCompatActivity implements LoaderManager.
     private TextView emptyState;
     private EditText searchInput;
     private ImageView sortImage;
+    private Utils.KeyboardStateMonitor keyboardStateMonitor;
 
     private interface SortClause {
         String NAME = Schema.AppMetadataTable.NAME + "." + Schema.AppMetadataTable.Cols.NAME + " asc";
@@ -57,6 +80,8 @@ public class AppListActivity extends AppCompatActivity implements LoaderManager.
 
         setContentView(R.layout.activity_app_list);
 
+        keyboardStateMonitor = new Utils.KeyboardStateMonitor(findViewById(R.id.app_list_root));
+
         searchInput = (EditText) findViewById(R.id.search);
         searchInput.addTextChangedListener(new CategoryTextWatcher(this, searchInput, this));
         searchInput.setOnEditorActionListener(new TextView.OnEditorActionListener() {
@@ -119,6 +144,13 @@ public class AppListActivity extends AppCompatActivity implements LoaderManager.
             @Override
             public void onClick(View v) {
                 searchInput.setText("");
+                searchInput.requestFocus();
+                if (!keyboardStateMonitor.isKeyboardVisible()) {
+                    InputMethodManager inputMethodManager =
+                            (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
+                    inputMethodManager.toggleSoftInputFromWindow(v.getApplicationWindowToken(),
+                            InputMethodManager.SHOW_FORCED, 0);
+                }
             }
         });
 

app/src/main/res/layout/activity_app_list.xml

@@ -2,6 +2,7 @@
 <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/app_list_root"
     android:orientation="vertical"
     android:layout_width="match_parent"
     android:layout_height="match_parent">