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      1 /*
      2  * Copyright (C) 2008 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package android.widget;
     18 
     19 import android.content.Context;
     20 import android.util.AttributeSet;
     21 import android.view.KeyEvent;
     22 import android.view.MotionEvent;
     23 import android.view.View;
     24 import android.view.View.OnLongClickListener;
     25 
     26 /**
     27  * This widget provides a simple utility for turning a continued long-press event
     28  * into a series of clicks at some set frequency. There is no actual 'zoom' functionality
     29  * handled by this widget directly. Instead, clients of this API should set up an
     30  * {@link View#setOnClickListener(OnClickListener) onClickListener} to handle
     31  * zoom functionality. That click listener is called on a frequency
     32  * determined by {@link #setZoomSpeed(long)} whenever the user long-presses
     33  * on the ZoomButton.
     34  *
     35  * @deprecated Use other means to handle this functionality. This widget is merely a
     36  * simple wrapper around a long-press handler.
     37  */
     38 @Deprecated
     39 public class ZoomButton extends ImageButton implements OnLongClickListener {
     40 
     41     private final Runnable mRunnable = new Runnable() {
     42         public void run() {
     43             if (hasOnClickListeners() && mIsInLongpress && isEnabled()) {
     44                 callOnClick();
     45                 postDelayed(this, mZoomSpeed);
     46             }
     47         }
     48     };
     49 
     50     private long mZoomSpeed = 1000;
     51     private boolean mIsInLongpress;
     52 
     53     public ZoomButton(Context context) {
     54         this(context, null);
     55     }
     56 
     57     public ZoomButton(Context context, AttributeSet attrs) {
     58         this(context, attrs, 0);
     59     }
     60 
     61     public ZoomButton(Context context, AttributeSet attrs, int defStyleAttr) {
     62         this(context, attrs, defStyleAttr, 0);
     63     }
     64 
     65     public ZoomButton(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
     66         super(context, attrs, defStyleAttr, defStyleRes);
     67         setOnLongClickListener(this);
     68     }
     69 
     70     @Override
     71     public boolean onTouchEvent(MotionEvent event) {
     72         if ((event.getAction() == MotionEvent.ACTION_CANCEL)
     73                 || (event.getAction() == MotionEvent.ACTION_UP)) {
     74             mIsInLongpress = false;
     75         }
     76         return super.onTouchEvent(event);
     77     }
     78 
     79     /**
     80      * Sets the delay between calls to the widget's {@link View#setOnClickListener(OnClickListener)
     81      * onClickListener}.
     82      *
     83      * @param speed The delay between calls to the click listener, in milliseconds
     84      */
     85     public void setZoomSpeed(long speed) {
     86         mZoomSpeed = speed;
     87     }
     88 
     89     @Override
     90     public boolean onLongClick(View v) {
     91         mIsInLongpress = true;
     92         post(mRunnable);
     93         return true;
     94     }
     95 
     96     @Override
     97     public boolean onKeyUp(int keyCode, KeyEvent event) {
     98         mIsInLongpress = false;
     99         return super.onKeyUp(keyCode, event);
    100     }
    101 
    102     @Override
    103     public void setEnabled(boolean enabled) {
    104         if (!enabled) {
    105 
    106             /* If we're being disabled reset the state back to unpressed
    107              * as disabled views don't get events and therefore we won't
    108              * get the up event to reset the state.
    109              */
    110             setPressed(false);
    111         }
    112         super.setEnabled(enabled);
    113     }
    114 
    115     @Override
    116     public boolean dispatchUnhandledMove(View focused, int direction) {
    117         clearFocus();
    118         return super.dispatchUnhandledMove(focused, direction);
    119     }
    120 
    121     @Override
    122     public CharSequence getAccessibilityClassName() {
    123         return ZoomButton.class.getName();
    124     }
    125 }
    126