Android小知识

Android小知识

1. 安卓全屏代码

    //安卓全屏代码
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
            WindowManager.LayoutParams.FLAG_FULLSCREEN);

2. 在Activity代码中设置背景图片.代码如下:

Drawable drawable = ContextCompat.getDrawable(RandomSelectionActivity.this,
                        R.drawable.hubian);
activity_random_selection.setBackground(drawable);

3. Android中在代码中布局的一些基础:

    //主布局
    LinearLayout mainLayout = new LinearLayout(this);
    mainLayout.setLayoutParams(new LinearLayout.LayoutParams(
            LinearLayout.LayoutParams.MATCH_PARENT,
            LinearLayout.LayoutParams.MATCH_PARENT
    ));
    mainLayout.setOrientation(LinearLayout.VERTICAL);   //设置方向是垂直

    //创建RelativeLayout对象
    RelativeLayout topRelativeLayout = new RelativeLayout(this);
    RelativeLayout bottomRelativeLayout = new RelativeLayout(this);

    // 建立布局样式宽和高，对应xml布局中：
    // android:layout_width="match_parent"
    // android:layout_height="0"
    //layout_weight=1
    topRelativeLayout.setLayoutParams(new LinearLayout.LayoutParams(
            RelativeLayout.LayoutParams.MATCH_PARENT,0,1
            ));
    bottomRelativeLayout.setLayoutParams(new LinearLayout.LayoutParams(
            RelativeLayout.LayoutParams.MATCH_PARENT,0,1
    ));

    //在代码中获取color
    //getColor(int id)在API版本23时(Android 6.0)已然过时    这里没办法,我的是android4.4
    topRelativeLayout.setBackgroundColor(getResources().getColor(R.color.colorBlueXfhy));
    bottomRelativeLayout.setBackgroundColor(getResources().getColor(R.color.colorEye));

    TextView player1TextView = new TextView(this);
    player1TextView.setId(generateViewId());   //直接使用 generateViewId() 获得ID，且可以得到不重复的ID
    player1TextView.setText("哈哈");
    player1TextView.setTextSize((float)30);   //文字大小
    player1TextView.setRotation((float)180);  //旋转角度
    RelativeLayout.LayoutParams player1TextViewLayoutParams = new RelativeLayout.LayoutParams(
      RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT
    );
    player1TextViewLayoutParams.addRule(ALIGN_PARENT_BOTTOM);    //父布局底部
    player1TextViewLayoutParams.bottomMargin = 40;       //距离底部40dp
    player1TextViewLayoutParams.addRule(RelativeLayout.CENTER_HORIZONTAL);  //水平居中

    // 在父类布局中添加它，及布局样式
    topRelativeLayout.addView(player1TextView,player1TextViewLayoutParams);
    mainLayout.addView(topRelativeLayout);
    mainLayout.addView(bottomRelativeLayout);
    return mainLayout;

这里的重写AppCompatActivity是为了更好为我们编写代码布局服务,需要的时候直接集继承自BaseActivity,然后就可以动态的加载布局了:

        public abstract class BaseActivity extends AppCompatActivity {
        public Handler handler;

        /** 初始化数据 */
        protected abstract void initData();

        /** 初始化资源 */
        protected abstract void initRecourse();

        /** 初始化界面 */
        protected abstract View initView();

        /** 处理handler回传的信息 */
        public void dispatchMessage(Message msg) {
        }

        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);

            requestWindowFeature(Window.FEATURE_NO_TITLE);
            //setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
            getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                    WindowManager.LayoutParams.FLAG_FULLSCREEN);//设置全屏

            initData();

            initRecourse();

            setContentView(initView());

            handler = new Handler() {
                public void dispatchMessage(Message msg) {
                    BaseActivity.this.dispatchMessage(msg);
                }
            };
        }
    }