chroe: add methods of components and optimization of code

Author: wenlng

projects/go-captcha-angular/src/lib/modules/click/click.component.ts

@@ -38,7 +38,7 @@ export class ClickComponent {
     }
 
     get hasDisplayImageState() {
-        return this.localData.image != '' && this.localData.thumb != ''
+        return this.localData.image != '' || this.localData.thumb != ''
     }
 
     clickEvent(e: Event|any){

projects/go-captcha-angular/src/lib/modules/rotate/rotate.component.html

@@ -40,7 +40,7 @@
       >
         <img
           [class]="{'gc-hide': localData.image == ''}"
-          [style]="{display: hasDisplayImageState ? 'block' : 'none'}"
+          [style]="{visibility: hasDisplayImageState ? 'visible' : 'hidden'}"
           [src]="localData.image"
           alt=""
         />

projects/go-captcha-angular/src/lib/modules/rotate/rotate.component.ts

@@ -135,7 +135,7 @@ export class RotateComponent {
             isMoving = false
             clearEvent()
 
-            if (currentAngle <= 0) {
+            if (currentAngle < 0) {
                 return
             }
 

projects/go-captcha-angular/src/lib/modules/slide-region/slide-region.component.ts

@@ -155,7 +155,7 @@ export class SlideRegionComponent {
             isMoving = false
             clearEvent()
 
-            if (tileLeft <= 0 || tileTop <= 0) {
+            if (tileLeft < 0 || tileTop < 0) {
                 return
             }
 

projects/go-captcha-angular/src/lib/modules/slide/slide.component.ts

@@ -145,7 +145,7 @@ export class SlideComponent {
             isMoving = false
             clearEvent()
 
-            if (currentThumbX <= 0) {
+            if (currentThumbX < 0) {
                 return
             }