Question

我准备了一个自定义视图＆amp;它被添加到一个activity.now上，根据我想要更改活动的内容，将在该视图上发生的事件。作为自定义视图类＆amp;活动类是不同的我无法处理它。请帮我解决这个问题。谢谢你们。

Answer 1

如果你必须更新Main_activity（包含视图）上的任何内容，那么你应该在自定义视图中创建一个Main_activity变量，如下所示：

private Main_activity activity;

然后你可以在主要活动中调用任何函数 update（），如下所示：

this.activity.update();

Answer 2

为了构建具有两个自定义视图的应用程序以及来自主要活动的自定义侦听器：

我知道在互联网/整个SO上有很多类似的帖子，但这个帖子很简单而且完整。

您的活动类：

public class MyActivity extends Activity{
  @Override
  protected void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);

    //initializing custom views
    MyCustomView1 myCustomView1 = new MyCustomView1(parameterList);
    MyCustomView2 myCustomView2 = new MyCustomView2(parameterList);

    //adding both custom views to the main activity
    mainView.addView(myCustomView1);
    mainView.addView(myCustomView1);

    //adding custom listener to the custom view 1
    myCustomView1.setCustomEventListener(new OnCustomEventListener() {

        @Override
        public void onEvent() {
            //firing an event of custom view 1
            Toast.makeText(MainActivity.this, "Touched custom view 1",
                    Toast.LENGTH_SHORT).show();
        }
    });

    //adding custom listener to the custom view 2
    myCustomView2.setCustomEventListener(new OnCustomEventListener() {

        @Override
        public void onEvent() {
            //firing an event of custom view 2
            Toast.makeText(MainActivity.this, "Touched custom view 2",
                    Toast.LENGTH_SHORT).show();
        }
    });
  }
}

您的MyCustomView1课程：

public class MyCustomView1 extends LinearLayout{
  OnCustomEventListener myCustomEventListener;

  public MyCustomView1(ParameterList){
    super(ContextFromParameterList);
    //Just adding something to the custom view 1 in order to distinguish it on the screen
    TextView tv = new TextView(ContextFromParameterList);
    tv.setText("Hello world from custom view 1");
    addView(tv);

    this.setOnTouchListener(new OnTouchListener() {

        @Override
        public boolean onTouch(View v, MotionEvent event) {
            //delegating one event to another (delegating touch event to custom event)
            if (MyCustomView1.this.myCustomEventListener != null)
                MyCustomView1.this.myCustomEventListener.onEvent();
            return false;
        }
    });
  }

  public void setCustomEventListener(OnCustomEventListener eventListener) {
    //setting custom listener from activity
    myCustomEventListener = eventListener;
  }
}

您的MyCustomView2课程：

public class MyCustomView2 extends LinearLayout {
OnCustomEventListener myCustomEventListener;

public MyCustomView2(ParameterList) {
    super(ContextFromParameterList);
    //Just adding something to the custom view 1 in order to distinguish it on the screen
    TextView tv = new TextView(ContextFromParameterList);
    tv.setText("Hello world from custom view 2");
    addView(tv);

    this.setOnTouchListener(new OnTouchListener() {

        @Override
        public boolean onTouch(View v, MotionEvent event) {
            //delegating one event to another (delegating touch event to custom event)
            if (MyCustomView2.this.myCustomEventListener != null)
                MyCustomView2.this.myCustomEventListener.onEvent();
            return false;
        }
    });
}

  public void setCustomEventListener(OnCustomEventListener eventListener) {
    //setting custom listener from activity
    myCustomEventListener = eventListener;
  }
}

您的侦听器界面：

public interface OnCustomEventListener{
  //interface defines one method. Can be more and methods may have parameters
  public void onEvent();
}

所以，不要像我在活动中那样展示祝酒词，而是按照自己的方式做到 - 隐藏一个视图，展示另一个视图等等。

如何从自定义视图处理事件以启动android中的活动

2 个答案: