CustomView保持同一高度

Question

我有這樣的自定義視圖：

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(); 

    } 
} 

有了這個佈局定義：

<?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> 

而且我希望把它放在多個佈局，所以我不喜歡這樣寫道：

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

但事實是，如果我想把這個多種佈局（70+），那麼我必須指定的每一個的高度和寬度它們。有沒有辦法在自定義視圖中強制執行高度？

如果我不指定目標佈局上的高度和寬度，那麼我得到一個錯誤。如果我把wrap_content的topbar_layout中指定的高度忽略。

Answer 1

您需要在您的自定義視圖實現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); 
}