Editext去掉视觉回显

(http://img.blog.csdn.net/20160627141407143)

public class AsteriskPasswordTransformationMethod extends
PasswordTransformationMethod {
@Override
public CharSequence getTransformation(CharSequence source, View view) {
return new PasswordCharSequence(source);
}

private class PasswordCharSequence implements CharSequence {
private CharSequence mSource;

public PasswordCharSequence(CharSequence source) {
mSource = source; // Store char sequence
}

public char charAt(int index) {
return '*'; // This is the important part
}

public int length() {
return mSource.length(); // Return default
}

public CharSequence subSequence(int start, int end) {
return mSource.subSequence(start, end); // Return default
}
}
}