有些页面中ListView只是整个页面的一小部分,需要上下滑动整个页面,ListView不让自己滑动,默认ListView只会显示第一个item。这个时候需要重新设置一下ListView的高度。如果ListView的item中有TextView并且TextView的行数大于1行,这个时候.重设ListView的高度却计算不出TextView的高度,会出现TextView只显示一行的情况。这个时候需要使用自定义的TextView,并且不要设置MaxLines这个属性。
设置ListView高度的代码:
public static void SetHeigth(ListView list) { ListAdapter listAdapter = list.getAdapter(); if (listAdapter == null) { return; } int totalHeight = 0; for (int i = 0, len = listAdapter.getCount(); i < len; i++) { View listItem = listAdapter.getView(i, null, list); // listItem.measure(LinearLayout.LayoutParams.MATCH_PARENT,0); listItem.measure(0,0); totalHeight += listItem.getMeasuredHeight(); } ViewGroup.LayoutParams params = list.getLayoutParams(); params.height = totalHeight+ (list.getDividerHeight() * (listAdapter.getCount() - 1)); list.setLayoutParams(params); }
自定义TextView的代码:
public class MyTextView extends TextView { private Context context; public MyTextView(Context context, AttributeSet attrs) { super(context, attrs); // TODO Auto-generated constructor stub this.context=context; } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { // TODO Auto-generated method stub super.onMeasure(widthMeasureSpec, heightMeasureSpec); Layout layout = getLayout(); if (layout != null) { int height = (int)Math.ceil(getMaxLineHeight(this.getText().toString())) + getCompoundPaddingTop() + getCompoundPaddingBottom(); int width = getMeasuredWidth(); setMeasuredDimension(width, height); } } private float getMaxLineHeight(String str){ float height = 0.0f; float screenW = context.getResources().getDisplayMetrics().widthPixels; float paddingLeft = ((LinearLayout)this.getParent()).getPaddingLeft(); float paddingReft = ((LinearLayout)this.getParent()).getPaddingRight(); //这里具体this.getPaint()要注意使用,要看你的TextView在什么位置,这个是拿TextView父控件的Padding的,为了更准确的算出换行 int line = (int) Math.ceil( (this.getPaint().measureText(str)/(screenW-paddingLeft-paddingReft))); height = (this.getPaint().getFontMetrics().descent-this.getPaint().getFontMetrics().ascent)*line; return height; } }