Android EditText搜索框实现图标居中

类似这样edittext 搜索框，hiht 提示有一个icon并且text内容。

重写edittext ：

package mobi.truekey.weapp2.widget;

import android.content.context;
import android.content.res.typedarray;
import android.graphics.canvas;
import android.graphics.paint;
import android.graphics.drawable.drawable;
import android.util.attributeset;
import android.widget.edittext;

import mobi.truekey.weapp2.r;

public class searchview extends edittext {

  private float searchsize = 0;
  private float textsize = 0;
  private int textcolor = 0xff000000;
  private drawable mdrawable;
  private paint paint;

  public searchview(context context, attributeset attrs) {
    super(context, attrs);
    initresource(context, attrs);
    initpaint();
  }

  private void initresource(context context, attributeset attrs) {
    typedarray mtypedarray = context.obtainstyledattributes(attrs, r.styleable.searchedit);
    float density = context.getresources().getdisplaymetrics().density;
    searchsize = mtypedarray.getdimension(r.styleable.searchedit_imagewidth, 18 * density + 0.5f);
    textcolor = mtypedarray.getcolor(r.styleable.searchedit_textcolor, 0xff848484);
    textsize = mtypedarray.getdimension(r.styleable.searchedit_textsize, 14 * density + 0.5f);
    mtypedarray.recycle();
  }

  private void initpaint() {
    paint = new paint(paint.anti_alias_flag);
    paint.setcolor(textcolor);
    paint.settextsize(textsize);
  }

  @override
  protected void ondraw(canvas canvas) {
    super.ondraw(canvas);
    drawsearchicon(canvas);
  }

  private void drawsearchicon(canvas canvas) {
    if (this.gettext().tostring().length() == 0) {
      float textwidth = paint.measuretext("搜索");
      float textheight = getfontleading(paint);

      float dx = (getwidth() - searchsize - textwidth - 8) / 2;
      float dy = (getheight() - searchsize) / 2;

      canvas.save();
      canvas.translate(getscrollx() + dx, getscrolly() + dy);
      if (mdrawable != null) {
        mdrawable.draw(canvas);
      }
      canvas.drawtext("搜索", getscrollx() + searchsize + 8, getscrolly() + (getheight() - (getheight() - textheight) / 2) - paint.getfontmetrics().bottom - dy, paint);
      canvas.restore();
    }
  }

  @override
  protected void onattachedtowindow() {
    super.onattachedtowindow();
    if (mdrawable == null) {
      try {
        mdrawable = getcontext().getresources().getdrawable(r.drawable.search);
        mdrawable.setbounds(0, 0, (int) searchsize, (int) searchsize);
      } catch (exception e) {

      }
    }
  }

  @override
  protected void ondetachedfromwindow() {
    if (mdrawable != null) {
      mdrawable.setcallback(null);
      mdrawable = null;
    }
    super.ondetachedfromwindow();
  }

  public float getfontleading(paint paint) {
    paint.fontmetrics fm = paint.getfontmetrics();
    return fm.bottom - fm.top;
  }

}

attr：

<declare-styleable name="searchedit">
  <attr name="imagewidth" format="dimension" />
  <attr name="textsize" format="dimension" />
  <attr name="textcolor" format="color" />
</declare-styleable>

drawable背景：

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
  <corners android:radius="6dp" />
  <solid android:color="@color/white" />

</shape>

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。