Question

我有这个自定义视图：

public class TopBarHandler extends FrameLayout {

    private Drawable mRightButtonSrc;
    private boolean mShowRightButton;
    private String mTitle;


    private ImageButton mHamburgerButton;
    private EllipsizingTextView mTitleTextView;
    private ImageButton mRightButton;
    private ProgressBar mProgressBar;


    public TopBarHandler(final Context context, final AttributeSet attrs) {
        super(context, attrs);
        initView();
        TypedArray a = getContext().obtainStyledAttributes(attrs, R.styleable.topbarMenu);
        mShowRightButton = a.getBoolean(R.styleable.topbarMenu_showRightButton, false);
        mRightButtonSrc = a.getDrawable(R.styleable.topbarMenu_rightButtonSrc);
        mTitle = a.getString(R.styleable.topbarMenu_titleText);
    }

    public TopBarHandler(final Context context) {
        super(context);
        initView();
    }

    private void initView() {
        View view = inflate(getContext(), R.layout.top_bar_layout, null);
        mHamburgerButton = (ImageButton) findViewById(R.id.top_bar_hamburger_button);
        mTitleTextView = (EllipsizingTextView) findViewById(R.id.top_bar_title);
        mRightButton = (ImageButton) findViewById(R.id.top_bar_right_button);
        mProgressBar = (ProgressBar) findViewById(R.id.top_bar_progress_bar);

        addView(view);
    }


    public interface TopBarListener {
        void onHamburgerButtonPressed();
        void onRightButtonPressed();

    }
}

使用此布局定义：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/top_bar_layout"
    android:layout_width="match_parent"
    android:layout_height="@dimen/height_top_bar"
    android:background="@drawable/gradient_top_bar"
    android:gravity="center_vertical">

    <ImageButton
        android:id="@+id/top_bar_hamburger_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_centerVertical="true"
        android:layout_marginLeft="@dimen/margin_objects_top_bar"
        android:src="@drawable/selector_menu_topbar"
        android:background="@null"/>

    <com.myproject.android.utilities.fonts.EllipsizingTextView
        android:id="@+id/top_bar_title"
        style="@style/bar_title_style"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:text="@string/CameraWizard_CameraWizard"
        android:textSize="@dimen/menu_top_bar_title_size"
        android:layout_marginLeft="@dimen/margin_top_bar_title"
        android:layout_toLeftOf="@+id/top_bar_right_button"
        android:layout_alignParentLeft="true"/>

    <ImageButton
        android:id="@+id/top_bar_right_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_centerVertical="true"
        android:layout_marginRight="@dimen/margin_objects_top_bar"
        android:background="@drawable/top_bar_search"
        android:visibility="invisible" />

    <ProgressBar
        android:id="@+id/top_bar_progress_bar"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_centerVertical="true"
        android:layout_marginRight="@dimen/margin_objects_top_bar"
        android:indeterminate="false"
        android:minHeight="50dp"
        android:minWidth="50dp"
        android:progress="1"
        android:visibility="gone" />
</RelativeLayout>

我想把它放在多个布局中，所以我这样做：

  <com.myproject.android.menu.TopBarHandler
        android:layout_height="@dimen/height_top_bar"
        android:layout_width="fill_parent"
        />

但问题是，如果我想将它放在多个布局（70+）中，那么我必须在每个布局中指定高度和宽度。有没有办法在自定义视图中强制执行高度？

如果我没有在目标布局上指定高度和宽度，那么我会收到错误。如果我放入wrap_content，则忽略topbar_layout中指定的高度。

Answer 1

您需要在自定义视图中实现onMeasure（）：

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

    // What is the desired size of the view?
    int desiredWidth = 250;
    int desiredHeight = 250;

    // The MeasureSpecs passed in will depend on the LayoutParams
    // applied to the view in xml or programmatically

    // Analyse the MeasureSpec for width and height separately like this:
    int widthMode = MeasureSpec.getMode(widthMeasureSpec);
    int widthSize = MeasureSpec.getSize(widthMeasureSpec);
    switch (widthMode) {
        case MeasureSpec.UNSPECIFIED:
            widthSize = desiredWidth;
            break;
        case MeasureSpec.AT_MOST:
            widthSize = Math.min(widthSize, desiredWidth);
            break;
        case MeasureSpec.EXACTLY:
            break;
        default:
    }
    int heightMode = MeasureSpec.getMode(heightMeasureSpec);
    int heightSize = MeasureSpec.getSize(heightMeasureSpec);
    switch (heightMode) {
        case MeasureSpec.UNSPECIFIED:
            heightSize = desiredHeight;
            break;
        case MeasureSpec.AT_MOST:
            heightSize = Math.min(heightSize, desiredHeight);
            break;
        case MeasureSpec.EXACTLY:
            break;
        default:
    }
    // You must call setMeasuredDimension()
    setMeasuredDimension(widthSize, heightSize);
}

CustomView保持相同的高度

1 个答案: