Android 遍历界面所有的View

news2024/11/19 3:17:24

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一、导读

我们继续总结学习，温故知新。

二、概览

本文讲述如何遍历获取页面中所有的view，并输出对应的id，textview文本内容，imageview实际大小及设置的图片大小。

可用于检测android应用中的大图。

三、实践

不多说，直接上代码，

图片大小检测思路。

    fun checkBitmapFromView(){
        //1、遍历activity中的各个View控件
        //2、获取View控件加载的Bitmap
        //3、对比Bitmap宽高与View宽高
    }

示例代码:
遍历获取所有的view，并输出相应的信息


    List<View> viewList=new ArrayList<>();
    @Override
    protected void onResume() {
        super.onResume();
        logoIcon.postDelayed(new Runnable() {
            @Override
            public void run() {
                getAllViews((ViewGroup) getWindow().getDecorView());
                for (View view: viewList) {

                    if(view instanceof TextView) {
                        Log.d("xyz", view.toString());
                        Log.d("xyz", ((TextView)view).getText().toString());

                    } else if(view instanceof ImageView) {
                        Log.d("xyz", view.toString());
                        checkBitmap(view, ((ImageView)view).getDrawable());
                    } else {
                        Log.d("xyz", view.toString());
                    }
                }
            }
        }, 3000);
    }


    //获取所有的子view，我们这里只保存imageview及textview，用于测试
    private List<View> getAllViews(ViewGroup viewGroup){
        for(int i=0;i< viewGroup.getChildCount(); i++){
            View view = viewGroup.getChildAt(i);
            if(view instanceof ViewGroup) {
                getAllViews((ViewGroup) view);
            } else {
                if(view instanceof ImageView || view instanceof TextView) {
                    viewList.add(view);
                }
                if(view.getVisibility() == View.VISIBLE) {
                }
            }
        }
        return viewList;
    }

ImageView大小检测


    private void checkBitmap(Object thiz, Drawable drawable) {
        if (drawable instanceof BitmapDrawable && thiz instanceof View) {
            final Bitmap bitmap = ((BitmapDrawable) drawable).getBitmap();

            final View view = (View) thiz;
            int width = view.getWidth();
            int height = view.getHeight();

            if (bitmap != null) {
                if (width > 0 && height > 0) {
                    // 图标宽高都大于view带下的2倍以上，则警告
                    if (bitmap.getWidth() >= (width << 1)
                            && bitmap.getHeight() >= (height << 1)) {
//                        warn(bitmap.getWidth(), bitmap.getHeight(), width, height, new RuntimeException("Bitmap size too large"));
                    }
                    warn(bitmap.getWidth(), bitmap.getHeight(), width, height, new RuntimeException("log"));
                } else {
                    final Throwable stackTrace = new RuntimeException();
                    view.getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
                        @Override
                        public boolean onPreDraw() {
                            int w = view.getWidth();
                            int h = view.getHeight();
                            if (w > 0 && h > 0) {
                                if (bitmap.getWidth() >= (w << 1)
                                        && bitmap.getHeight() >= (h << 1)) {
//                                    warn(bitmap.getWidth(), bitmap.getHeight(), w, h, stackTrace);
                                }
                                warn(bitmap.getWidth(), bitmap.getHeight(), w, h, stackTrace);
                                view.getViewTreeObserver().removeOnPreDrawListener(this);
                            }
                            return true;
                        }
                    });
                }
            } else {

                warn(bitmap.getWidth(), bitmap.getHeight(), width, height, new RuntimeException("bitmap null"));
            }
        }
    }

    private void warn(int bitmapWidth, int bitmapHeight, int viewWidth, int viewHeight, Throwable t) {
        String warnInfo = new StringBuilder("Bitmap info: ")
                .append("\n real size: (").append(bitmapWidth).append(',').append(bitmapHeight).append(')')
                .append("\n desired size: (").append(viewWidth).append(',').append(viewHeight).append(')')
                .append("\n call stack trace: \n").append(Log.getStackTraceString(t)).append('\n')
                .toString();

        Log.d("xyz", warnInfo);
    }

我们看下log输出

com.xxx.xxx.xxx.ImageViewFor{e292c7e VFED..C.. ........ 540,1348-900,1528 #7f0a024e app:id/bt_phone}
2023-08-23 18:28:47.956 12556-12556 xyz                com.xxx.xxx                      D  Bitmap info: 
         real size: (144,144)
         desired size: (360,180)
         call stack trace: 
        java.lang.RuntimeException: log
            at com.xxx.xxx.ui.LoginActivity.checkBitmap(LoginActivity.java:235)
            at com.xxx.xxx.ui.LoginActivity.access$100(LoginActivity.java:79)
            at com.xxx.xxx.ui.LoginActivity$2.run(LoginActivity.java:193)
            at android.os.Handler.handleCallback(Handler.java:900)
            at android.os.Handler.dispatchMessage(Handler.java:103)
            at android.os.Looper.loop(Looper.java:219)
            at android.app.ActivityThread.main(ActivityThread.java:8673)
            at java.lang.reflect.Method.invoke(Native Method)
            at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:513)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1109)