/*
 * Copyright (C) 2008 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.widget;

import android.annotation.Widget;
import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.animation.AlphaAnimation;

import com.android.internal.R;


The ZoomControls class displays a simple set of controls used for zooming and provides callbacks to register for events.
/** * The {@code ZoomControls} class displays a simple set of controls used for zooming and * provides callbacks to register for events. */
@Widget public class ZoomControls extends LinearLayout { private final ZoomButton mZoomIn; private final ZoomButton mZoomOut; public ZoomControls(Context context) { this(context, null); } public ZoomControls(Context context, AttributeSet attrs) { super(context, attrs); setFocusable(false); LayoutInflater inflater = (LayoutInflater) context .getSystemService(Context.LAYOUT_INFLATER_SERVICE); inflater.inflate(R.layout.zoom_controls, this, // we are the parent true); mZoomIn = (ZoomButton) findViewById(R.id.zoomIn); mZoomOut = (ZoomButton) findViewById(R.id.zoomOut); } public void setOnZoomInClickListener(OnClickListener listener) { mZoomIn.setOnClickListener(listener); } public void setOnZoomOutClickListener(OnClickListener listener) { mZoomOut.setOnClickListener(listener); } /* * Sets how fast you get zoom events when the user holds down the * zoom in/out buttons. */ public void setZoomSpeed(long speed) { mZoomIn.setZoomSpeed(speed); mZoomOut.setZoomSpeed(speed); } @Override public boolean onTouchEvent(MotionEvent event) { /* Consume all touch events so they don't get dispatched to the view * beneath this view. */ return true; } public void show() { fade(View.VISIBLE, 0.0f, 1.0f); } public void hide() { fade(View.GONE, 1.0f, 0.0f); } private void fade(int visibility, float startAlpha, float endAlpha) { AlphaAnimation anim = new AlphaAnimation(startAlpha, endAlpha); anim.setDuration(500); startAnimation(anim); setVisibility(visibility); } public void setIsZoomInEnabled(boolean isEnabled) { mZoomIn.setEnabled(isEnabled); } public void setIsZoomOutEnabled(boolean isEnabled) { mZoomOut.setEnabled(isEnabled); } @Override public boolean hasFocus() { return mZoomIn.hasFocus() || mZoomOut.hasFocus(); } @Override public CharSequence getAccessibilityClassName() { return ZoomControls.class.getName(); } }