如何在android中的webview上获得onclick事件？

Question

我想知道用户何时点击webview而不是超链接.在该单击时,我想显示/隐藏包含webview的活动视图.有什么建议吗？

Answer 1

我看了一下这个,我发现a WebView似乎没有发送点击事件OnClickListener.如果那里的任何人可以证明我错了或告诉我为什么然后我有兴趣听到它.

我找到的是一个WebView会发送触摸事件给一个OnTouchListener.它确实有自己的onTouchEvent方法,但我似乎只是MotionEvent.ACTION_MOVE使用该方法.

因此,考虑到我们可以在已注册的触摸事件监听器上获取事件,剩下的唯一问题是如何在用户单击URL时绕过您想要执行的任何操作.

这可以通过一些花哨的Handler步法来实现,通过发送延迟的触摸消息,然后如果用户点击URL引起触摸则移除那些触摸消息.

这是一个例子:

public class WebViewClicker extends Activity implements OnTouchListener, Handler.Callback {

private static final int CLICK_ON_WEBVIEW = 1;
private static final int CLICK_ON_URL = 2;

private final Handler handler = new Handler(this);

private WebView webView;
private WebViewClient client;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.web_view_clicker);

    webView = (WebView)findViewById(R.id.web);
    webView.setOnTouchListener(this);

    client = new WebViewClient(){ 
        @Override public boolean shouldOverrideUrlLoading(WebView view, String url) { 
            handler.sendEmptyMessage(CLICK_ON_URL);
            return false;
        } 
    }; 

    webView.setWebViewClient(client);
    webView.setVerticalScrollBarEnabled(false);
    webView.loadUrl("http://www.example.com");
}

@Override
public boolean onTouch(View v, MotionEvent event) {
    if (v.getId() == R.id.web && event.getAction() == MotionEvent.ACTION_DOWN){
        handler.sendEmptyMessageDelayed(CLICK_ON_WEBVIEW, 500);
    }
    return false;
}

@Override
public boolean handleMessage(Message msg) {
    if (msg.what == CLICK_ON_URL){
        handler.removeMessages(CLICK_ON_WEBVIEW);
        return true;
    }
    if (msg.what == CLICK_ON_WEBVIEW){
        Toast.makeText(this, "WebView clicked", Toast.LENGTH_SHORT).show();
        return true;
    }
    return false;
}
}

希望这可以帮助.

Answer 2

您可以通过OnTouchListener实现OnClickListener:

webView.setOnTouchListener(new View.OnTouchListener() {

        public final static int FINGER_RELEASED = 0;
        public final static int FINGER_TOUCHED = 1;
        public final static int FINGER_DRAGGING = 2;
        public final static int FINGER_UNDEFINED = 3;

        private int fingerState = FINGER_RELEASED;


        @Override
        public boolean onTouch(View view, MotionEvent motionEvent) {

            switch (motionEvent.getAction()) {

                case MotionEvent.ACTION_DOWN:
                    if (fingerState == FINGER_RELEASED) fingerState = FINGER_TOUCHED;
                    else fingerState = FINGER_UNDEFINED;
                    break;

                case MotionEvent.ACTION_UP:
                    if(fingerState != FINGER_DRAGGING) {
                        fingerState = FINGER_RELEASED;

                        // Your onClick codes

                    }
                    else if (fingerState == FINGER_DRAGGING) fingerState = FINGER_RELEASED;
                    else fingerState = FINGER_UNDEFINED;
                    break;

                case MotionEvent.ACTION_MOVE:
                    if (fingerState == FINGER_TOUCHED || fingerState == FINGER_DRAGGING) fingerState = FINGER_DRAGGING;
                    else fingerState = FINGER_UNDEFINED;
                    break;

                default:
                    fingerState = FINGER_UNDEFINED;

            }

            return false;
        }
    });

Answer 3

Hamidreza的解决方案几乎对我有用.

我从实验中注意到,简单的点击通常有2-5个动作移动事件.检查操作向下和向上之间的时间更简单,表现得更像我的预期.

private class CheckForClickTouchLister implements View.OnTouchListener {
    private final static long MAX_TOUCH_DURATION = 100;

    @Override
    public boolean onTouch(View v, MotionEvent event) {

        switch (event.getAction()) {

            case MotionEvent.ACTION_DOWN:
                m_DownTime = event.getEventTime(); //init time

                break;

            case MotionEvent.ACTION_UP:
                if(event.getEventTime() - m_DownTime <= MAX_TOUCH_DURATION)
                    //On click action

                break;

            default:
                break; //No-Op

        }
        return false;
    }

Answer 4

On Click事件on webView在onTouch中工作如下:

imagewebViewNewsChart.setOnTouchListener(new View.OnTouchListener(){

  @Override   
  public boolean onTouch(View v, MotionEvent event) { 
    if (event.getAction()==MotionEvent.ACTION_MOVE){                        
       return false;     
    }

    if (event.getAction()==MotionEvent.ACTION_UP){    
        startActivity(new Intent(this,Example.class));                

    } 

    return false;                 
  }                       
});