变换颜色小试

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="${relativePackage}.${activityClass}">

    <TextView
        android:id="@+id/tv"
        android:textSize="40dip"
        android:text="@string/hello_world"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <Button
        android:id="@+id/btn"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="改变字体颜色"
        />
</LinearLayout>

MainActivity.java

public class MainActivity extends Activity {

    private Button btnn;
    private TextView tvv;
    private int[] colorArray;
    private int colorNum;
    private String strColor[];

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        btnn = (Button) findViewById(R.id.btn);
        tvv = (TextView) findViewById(R.id.tv);

        colorArray = new int[]{Color.YELLOW, Color.BLUE, Color.GREEN};
        strColor = new String[]{"黄色", "蓝色", "绿色"};
        colorNum = 0;
        btnn.setOnClickListener(new Button.OnClickListener() {
                                    @Override
                                    public void onClick(View v) {
                                        if (colorNum < colorArray.length) {

                                            tvv.setTextColor(colorArray[colorNum]);
                                            Toast toast = Toast.makeText(MainActivity.this, "此时文字颜色为" + strColor[colorNum], Toast.LENGTH_SHORT);
                                            toast.setGravity(Gravity.TOP, 0, 150);
                                            toast.show();
                                            colorNum++;

                                        } else colorNum = 0;

                                    }
                                }
        );

    }
}