android - 关于videoview布局的问题

Question

新手，看到视频播放的时候，动手弄了个最简单的布局
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<VideoView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/vv_show"/>

</LinearLayout>

在VideoVidw里面设置layout_width,layout_height,不管设置成match_parent还是wrap_content的，这个VideoView还是撑满了整个屏幕（程序就是一个简单的布局，除了自动代码以外，没有加一点代码），发现这里wrap_content就一点用都没有，请教前辈这个是什么问题

Answer 1

Untuk masalah saiz, sila rujuk kaedah VideoView onMeasure()

Saiz

VideoView berkaitan dengan mVideoWidth dan mVideoHeight Anda boleh lihat daripada nama pembolehubah bahawa ia adalah saiz sebenar media yang akan dimainkan pandangan kasar pada onMeasure(), logik di dalamnya tidak Ia sangat rumit anda boleh melihatnya sendiri dan anda mungkin akan tahu apa masalahnya

Answer 2

Secara umumnya, pemain perlu menentukan saiznya sendiri kerana ia akan berskala dan tidak boleh menggunakan kaedah definisi ketinggian untuk membungkus kandungan.

Seperti yang dinyatakan di tingkat satu, untuk memahami proses pemaparan reka letak VideoView, anda boleh melihat kod sumber VideoView

Kod sumber mengandungi
// no size yet, just adopt the given spec sizes
Jika anda tidak menetapkan ketinggian, ia akan memberi anda saiz ruang lalai, iaitu saiz bekas induk. Ia adalah skrin penuh.

@Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        //Log.i("@@@@", "onMeasure(" + MeasureSpec.toString(widthMeasureSpec) + ", "
        //        + MeasureSpec.toString(heightMeasureSpec) + ")");

        int width = getDefaultSize(mVideoWidth, widthMeasureSpec);
        int height = getDefaultSize(mVideoHeight, heightMeasureSpec);
        if (mVideoWidth > 0 && mVideoHeight > 0) {

            int widthSpecMode = MeasureSpec.getMode(widthMeasureSpec);
            int widthSpecSize = MeasureSpec.getSize(widthMeasureSpec);
            int heightSpecMode = MeasureSpec.getMode(heightMeasureSpec);
            int heightSpecSize = MeasureSpec.getSize(heightMeasureSpec);

            if (widthSpecMode == MeasureSpec.EXACTLY && heightSpecMode == MeasureSpec.EXACTLY) {
                // the size is fixed
                width = widthSpecSize;
                height = heightSpecSize;

                // for compatibility, we adjust size based on aspect ratio
                if ( mVideoWidth * height  < width * mVideoHeight ) {
                    //Log.i("@@@", "image too wide, correcting");
                    width = height * mVideoWidth / mVideoHeight;
                } else if ( mVideoWidth * height  > width * mVideoHeight ) {
                    //Log.i("@@@", "image too tall, correcting");
                    height = width * mVideoHeight / mVideoWidth;
                }
            } else if (widthSpecMode == MeasureSpec.EXACTLY) {
                // only the width is fixed, adjust the height to match aspect ratio if possible
                width = widthSpecSize;
                height = width * mVideoHeight / mVideoWidth;
                if (heightSpecMode == MeasureSpec.AT_MOST && height > heightSpecSize) {
                    // couldn't match aspect ratio within the constraints
                    height = heightSpecSize;
                }
            } else if (heightSpecMode == MeasureSpec.EXACTLY) {
                // only the height is fixed, adjust the width to match aspect ratio if possible
                height = heightSpecSize;
                width = height * mVideoWidth / mVideoHeight;
                if (widthSpecMode == MeasureSpec.AT_MOST && width > widthSpecSize) {
                    // couldn't match aspect ratio within the constraints
                    width = widthSpecSize;
                }
            } else {
                // neither the width nor the height are fixed, try to use actual video size
                width = mVideoWidth;
                height = mVideoHeight;
                if (heightSpecMode == MeasureSpec.AT_MOST && height > heightSpecSize) {
                    // too tall, decrease both width and height
                    height = heightSpecSize;
                    width = height * mVideoWidth / mVideoHeight;
                }
                if (widthSpecMode == MeasureSpec.AT_MOST && width > widthSpecSize) {
                    // too wide, decrease both width and height
                    width = widthSpecSize;
                    height = width * mVideoHeight / mVideoWidth;
                }
            }
        } else {
            // no size yet, just adopt the given spec sizes
        }
        setMeasuredDimension(width, height);
    }