Android复合 View : cannot make child view match parent

我创建了一个自定义 View (复合 View )，该 View 继承自FrameLayout并在其中包含几个 subview :

MediaComponentView.java:

final public class MediaComponentView extends FrameLayout {
    private int ratio = 1;

    private ImageView imageView;
    private CircularProgressView progressView;
    private View downloadButton;
    private View cancelButton;
    private View playButton;

    public MediaComponentView(Context context) {
        super(context);
        initializeViews();
    }

    public MediaComponentView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initializeViews();
    }

    public MediaComponentView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        initializeViews();
    }

    private void initializeViews() {
        inflate(getContext(), R.layout.view_media_component, this);
    }

    @Override
    protected void onFinishInflate() {
        super.onFinishInflate();

        imageView = (ImageView) this.findViewById(R.id.image_view);
        progressView = (CircularProgressView) this.findViewById(R.id.progress_view);
        downloadButton = this.findViewById(R.id.download_button);
        cancelButton = this.findViewById(R.id.cancel_button);
        playButton = this.findViewById(R.id.play_button);
    }

    public void setRatio(int ratio) {
        this.ratio = ratio;
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        setMeasuredDimension(getMeasuredWidth(), getMeasuredWidth() / ratio);
    }

}

view_media_component.xml:

<merge
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    >

    <com.makeramen.roundedimageview.RoundedImageView
        android:id="@+id/image_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scaleType="centerCrop"
        app:riv_border_color="#eee"
        app:riv_border_width="1px"
        app:riv_corner_radius="3dp"
        />

    <com.github.rahatarmanahmed.cpv.CircularProgressView
        android:id="@+id/progress_view"
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:layout_gravity="center"
        android:visibility="gone"
        />

    <ImageView
        android:id="@+id/download_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:src="@drawable/icon_chat_media_download"
        android:visibility="gone"
        />

    <ImageView
        android:id="@+id/cancel_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:src="@android:drawable/ic_menu_close_clear_cancel"
        android:visibility="gone"
        />

    <ImageView
        android:id="@+id/play_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:src="@drawable/icon_chat_media_play"
        android:visibility="gone"
        />
</merge>

复合 View 的用法:

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal"
    android:layout_marginTop="4dp"
    android:layout_marginLeft="2dp"
    android:layout_marginRight="2dp"
    >

    <some.hidden.package.MediaComponentView
        android:id="@+id/media_0"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:layout_marginLeft="2dp"
        android:layout_marginRight="2dp"
        android:background="#00ff00"
        />

    <some.hidden.package.MediaComponentView
        android:id="@+id/media_1"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:layout_marginLeft="2dp"
        android:layout_marginRight="2dp"
        android:background="#ff0000"
        />
</LinearLayout>

问题是“image_view”的布局不正确。它与父项不匹配。

我已经通过设置背景来检查MediaComponentView本身的大小是否正确。它的大小正确。

但是 subview 的尺寸不正确。我猜是因为MediaComponentView中的onMeasure()方法被覆盖了。

任何帮助或解释将不胜感激。

最佳答案

您需要在onMeasure()覆盖的结尾处调用measureChildren(int widthMeasureSpec，int heightMeasureSpec)。 subview 不知道您更改了高度。