大三小学期 Android开发的一些经验

1.同一个TextView几种颜色的设置:

build=(TextView)findViewById(R.id.building);
SpannableStringBuilder style = new SpannableStringBuilder("建筑物名称*");
style.setSpan(new ForegroundColorSpan(Color.BLACK), 0, 5, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
style.setSpan(new ForegroundColorSpan(Color.RED), 5, 6, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
build.setText(style);
显示出来就是:建筑物名称*
 
2.判断输入不为空:
//建筑物名称不能为空
building.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) { } @Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
if(TextUtils.isEmpty(building.getText())||TextUtils.isEmpty(floor.getText())
||TextUtils.isEmpty(telephone.getText())||TextUtils.isEmpty(description.getText()))
{
upload.setEnabled(false);
Toast.makeText(Feedback.this,"请完成反馈信息的填写",Toast.LENGTH_LONG).show();
}
else
{
upload.setEnabled(true);
} } @Override
public void afterTextChanged(Editable s) { }
});
3.两个界面之间传递值,值为double类型:
发送方:
Intent intent = new Intent(selectPoint.this,Feedback.class);
intent.putExtra("latitude",latitude);
intent.putExtra("longtitude",longtitude);
startActivity(intent);

接收方:

Intent intent=getIntent();
final double longtitude = intent.getDoubleExtra("longtitude",0);
final double latitude = intent.getDoubleExtra("latitude",0);

4.设置app开头动态效果(转自:http://blog.csdn.net/nmsoftklb/article/details/12943483)

public class Welcome extends AppCompatActivity {
private ImageView welcome;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_welcome); welcome = (ImageView) this.findViewById(R.id.welcome);
AlphaAnimation anima = new AlphaAnimation(0.3f, 1.0f);
anima.setDuration(3000);// 设置动画显示时间
welcome.startAnimation(anima);
anima.setAnimationListener(new AnimationImpl());
} private class AnimationImpl implements Animation.AnimationListener { @Override
public void onAnimationStart(Animation animation) {
welcome.setBackgroundResource(R.drawable.welcome);
} @Override
public void onAnimationEnd(Animation animation) {
skip(); // 动画结束后跳转到别的页面
} @Override
public void onAnimationRepeat(Animation animation) { } } private void skip() {
startActivity(new Intent(this, Feedback.class));
finish();
}
}

5.去掉界面上面的蓝色默认的头

public class Award extends AppCompatActivity
改成
public class Award extends Activity

6.edittext提示为android:hint,edittext默认text为android:text

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