Android复合视图：无法使子视图匹配父级

我创建了一个自定义视图(复合视图),它继承自FrameLayout并包含多个子视图：

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>

使用复合视图：

<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”没有正确布局.它与父母不匹配.

我通过设置背景来检查MediaComponentView本身是否具有正确的大小.它的大小正确.

但是子视图的大小不正确.我想这是因为MediaComponentView中的覆盖onMeasure()方法.

任何帮助或解释将不胜感激.

解决方法:

您需要在onMeasure()覆盖的末尾调用measureChildren(int widthMeasureSpec,int heightMeasureSpec).子视图不知道您改变了高度.

标签：android,android-custom-view,layout-inflater,android-viewgroup
来源： https://codeday.me/bug/20190519/1136411.html