Android-全局布局侦听器不起作用 [英] Android - Global Layout Listener not working

问题描述

我在此问题.当我将其粘贴到代码中时，在addOnGlobalLayoutListener(new OnGlobalLayoutListener()，onGlobalLayout()和activityRootView(在heightDiff之后)下方出现红色的弯曲.请帮助我找出问题所在.

I used the code from Reuben Scratton's new answer in this question. When I paste it into my code, I get red squigglies underneath addOnGlobalLayoutListener(new OnGlobalLayoutListener(), onGlobalLayout(), and activityRootView (after heightDiff). Please help me figure out what is wrong.

谢谢 这是我在.java页面上的代码

Thanks Here's my code on the .java page

public class Details extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    this.requestWindowFeature(Window.FEATURE_NO_TITLE);
    setContentView(R.layout.activity_details);
    Intent intent = getIntent();        
}


final View activityRootView = findViewById(R.id.details);
activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {

    @Override
    public void onGlobalLayout() {
        int heightDiff = activityRootView.getRootView().getHeight() - activityRootView.getHeight();
        if (heightDiff > 100) { // if more than 100 pixels, its probably a keyboard...
            ImageButton backButton = (ImageButton)findViewById(R.id.back); 
            backButton.setImageResource(R.drawable.hide_keyboard);
        }
     }
});

推荐答案

您需要将该代码添加到方法中，例如onCreate().

You need to add that code inside a method, like onCreate().

public class Details extends Activity {
    View activityRootView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_details);
        Intent intent = getIntent();        

        activityRootView = findViewById(R.id.details);    
        activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                int heightDiff = activityRootView.getRootView().getHeight() - activityRootView.getHeight();
                if (heightDiff > 100) { // if more than 100 pixels, its probably a keyboard...
                    ImageButton backButton = (ImageButton)findViewById(R.id.back); 
                    backButton.setImageResource(R.drawable.hide_keyboard);
                }
             }
        });
    }
}

这篇关于Android-全局布局侦听器不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！