Electronic device and method for controlling zooming of displayed object
An electronic device and a method for controlling zooming of a displayed object includes receiving a single-point slide operation performed by a user on a displayed object of a touch screen, generating a slide signal, parsing the slide signal to obtain a slide track and a feature value of the single-point slide operation, determining whether the feature value of at least one point in the single-point slide operation is greater than a preset value, and controlling zooming of the displayed object according to the slide track when the feature value is greater than the preset value. A slide track and a feature value of a single-point slide operation of a user are identified, and zooming of a displayed object of the touch screen is controlled when the feature value is greater than a preset value.
1. A method for controlling zooming of a displayed object, comprising:
receiving a slide operation from a user on the displayed object of a touch screen;
calculating a starting point line (L 1 ) of the slide operation, the L 1 extending from a reference point to a starting point of the slide operation, the reference point having coordinates (X 0 , Y 0 ), and the starting point having coordinates (X, Y);
calculating an end point line (L 2 ) of the slide operation, the L 2 extending from the reference point to an ending point of the slide operation, and the ending point having coordinates (X i , Y i );
calculating a reference angle (q) according to an equation q=tan −1 (|Y−Y 0 |/|X−X 0 );
calculating a current angle (p) according to an equation p=tan −1 (|Y i −Y 0 |/|X i −X 0 ));
calculating a deflection angle (α) according to an equation α=p−q;
zooming in the displayed object when the α is less than zero; and
zooming out the displayed object when the α is greater than or equal to zero.
2. The method of claim 1 , wherein the slide operation is parsed to obtain a slide track.
3. The method of claim 1 , wherein a touch point in the click operation is a last touch point in the click operation.
4. The method of claim 1 , wherein zooming the displayed object comprises zooming the displayed object according to a correspondence between a preset number and a first zooming scale, and a center point of the displayed object is at a center.
5. The method of claim 1 , wherein the reference point on the touch screen comprises a bottom edge of the touch screen.
6. The method of claim 1 , wherein the reference point on the touch screen comprises a center of the touch screen.
7. The method of claim 1 , wherein the reference point on the touch screen comprises a vertex of the touch screen.
8. An electronic device, comprising:
a touch screen configured to receive a slide operation from a user on a displayed object of the touch screen; and
a processor coupled to the touch screen and configured to:
calculate a starting point line (L 1 ) of the slide operation, the L 1 extending from a reference point to a starting point of the slide operation, the reference point having coordinates (X 0 , Y 0 ), and the starting point having coordinates (X, Y);
calculate an end point line (L 2 ) of the slide operation, the L 2 extending from the reference point to an ending point of the slide operation, and the ending point having coordinates (X i , Y i );
calculate a reference angle (q) according to an equation q=tan −1 (|Y−Y 0 |/|X−X 0 );
calculate a current angle (p) according to an equation p=tan −1 (|Y i −Y 0 |/|X i −X 0 ));
calculate a deflection angle (α) according to an equation α=p−q;
controlling zooming in of the displayed object when the α is less than zero; and
controlling zooming out of the displayed object when the α is greater than or equal to zero.
9. The electronic device of claim 8 , where the slide operation is parsed to obtain a slide track.
10. The electronic device of claim 8 , wherein a touch point in the click operation is a last touch point in the click operation.
11. The electronic device of claim 8 , wherein the processor is further configured to control zooming the displayed object according to a correspondence between a preset number and a first zooming scale, and a center point of the displayed object is at a center.
12. The electronic device of claim 8 , wherein the reference point on the touch screen comprises a bottom edge of the touch screen.
13. The electronic device of claim 8 , wherein the reference point on the touch screen comprises a center of the touch screen.
14. The electronic device of claim 8 , wherein the reference point on the touch screen comprises a vertex of the touch screen.