读取layout属性-AttributeSet TypedArray

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假如说要读取layout_height属性

两种方式，第一种

  /**     * Returns the value of the specified attribute as a string representation.     *      * @param index Index of the desired attribute, 0...count-1.     *      * @return A String containing the value of the attribute, or null if the     *         attribute cannot be found.     */    public String getAttributeValue(int index);String namespace = "http://schemas.android.com/apk/res/android";viewHeight = attrs.getAttributeIntValue(namespace, "layout_height", ViewGroup.LayoutParams.MATCH_PARENT);

layout_height=“match_parent”

viewHeight 取到的值为 “match_parent”

layout_height=“100dip”

viewHeight 取到的值为 “100dip”

如果用 getAttributeIntValue 读取的话, 无法正确读取到数值

 /**     * Return the integer value of 'attribute'.     *      * @param namespace Namespace of attribute to retrieve.     * @param attribute The attribute to retrieve.     * @param defaultValue What to return if the attribute isn't found.     *      * @return Resulting value.     */    public int getAttributeIntValue(String namespace, String attribute, int defaultValue);

很显然这种方式读取数值不是很爽

第二种方式: 通过TypedArray读取

int[] arr = new int[] { android.R.attr.layout_width, android.R.attr.layout_height };TypedArray typedArray = context.obtainStyledAttributes(attrs, arr);// MATCH_PARENT -1 WRAP_CONTENT-2try {// String namespace = "http://schemas.android.com/apk/res/android";// initViewHeight = attrs.getAttributeIntValue(namespace, "layout_height", ViewGroup.LayoutParams.MATCH_PARENT);TypedValue typeValue = typedArray.peekValue(1);if (typeValue.type == TypedValue.TYPE_DIMENSION) {// 0x10initViewHeight = (int) typedArray.getDimension(1, ViewGroup.LayoutParams.MATCH_PARENT);initViewHeight = TypedValue.complexToDimensionPixelSize(typeValue.data, getResources().getDisplayMetrics());} else if (typeValue.type == TypedValue.TYPE_FIRST_INT) {// 0x05initViewHeight = typeValue.data;}} catch (Exception e) {// java.lang.UnsupportedOperationException: Can't convert to dimension: type=0x10e.printStackTrace();}typedArray.recycle();

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